THE EARTH 137 



of the world where the winds, that with us are so uncertain, pay theii 

 stated visits. In some places they are found to blow one way by day, 

 and another by night ; in others, for one half* of the year they go io 

 a direction contrary to their former course : but what is more extraor 

 dinarv still, there are some places where the winds never change, bin 

 for ever blow the same way. This is particularly found to obtain be- 

 tween the tropics in the Atlantic and jEthiopic oceans ; as well as 

 in the great Pacific sea. 



Few things can appear more extraordinary to a person who has 

 never been out of our variable latitudes, than this steady wind, that 

 for ever sits in the sail, sending the vessel forward ; and as effectually 

 preventing its return. He who has been taught to consider that nothing 

 in the world is so variable as the winds, must certainly be surprised 

 to find a place where there is nothing more uniform. With us their 

 inconstancy has become a proverb ; with the natives of those distant 

 climates they may talk of a friend or a mistress as fixed and un- 

 changeable as the winds, and mean a compliment by the comparison. 

 When our ships are once arrived into the proper latitudes of the great 

 Pacific ocean, the mariner forgets the helm, and his skill becomes al- 

 most useless : neither storms nor tempests are known to deform the 

 glassy bosom of that immense sheet of waters : a gentle breeze, that 

 forever blows in the same direction, rests upon the canvass, and speeds 

 the navigator. In the space of six weeks, ships are thus known to 

 cross an immense ocean, that takes more than so many m'onths to re- 

 turn. Upon returning, the trade-wind, which has been propitious, is 

 then avoided ; the mariner is generally obliged to steer into the 

 northern latitudes, and to take the advantage of every casual wind that 

 offers, to assist him into port. This wind, which blows with such con- 

 stancy one way, is known to prevail not only in the Pacific ocean, 

 but also in the Atlantic, between the coasts of Guinea and Brazil ; and, 

 likewise, in the ^Ethiopic ocean. This seems to be the great univer- 

 sal wind, blowing from the east to the west, that prevails in all the 

 extensive oceans, where the land does not frequently break the gene- 

 ral current. Were the whole surface of the globe an ocean, there 

 would probably be but this one wind, for ever blowing from the east, 

 and pursuing the motions of the sun westward. All the other winds 

 seem subordinate to this ; and many of them are made from the devi- 

 ations of its current. To form, therefore, any conception relative to 

 the variations of the wind in general, it is proper to begin with that 

 which never varies. 



There have been many theories to explain this invariable motion of 

 the winds ; among the rest, we cannot omit that of Dr. Lyster, for its 

 strangeness. " The sea," says he, " in those latitudes, is generally 

 covered over with green weeds, for a great extent ; and the air pro- 

 iuced from the vegetable perspiration of these, produces the trade- 

 wind." The theory of Cartesius was not quite so absurd. He al- 

 leged, that the earth went round faster than its atmosphere at the 

 equator ; so that its motion, from west to east, gave the atmosphere 

 an imaginary one from east to west ; and thus an east wind was eter- 

 nally seen to prevail. Rejecting those arbitrary opinions, conceiv 

 ed without force, and asserted without proof, Dr. Hallev has given 



